The aim of the Danish meta-analysis «Mikkelsen MB, Rosholm M. Systematic review and met...»1 was to collate and update the existing evidence for interventions aimed at facilitating RTW in sick-listed workers with mental disorders. Interventions aimed at a broad spectrum of high-prevalence, high-cost mental disorders (ie, anxiety disorders, depressive disorders, adjustment disorders, stress-related disorders, personality disorders and somatoform disorders) were included. EconLit, Embase, PsychInfo, PubMed, Svemed+ and Web of Science were searched from January 2000 to June 2017 for peerreviewed, randomised or controlled studies assessing employment-related outcomes of interventions. Peer-reviewed, randomised or controlled studies assessing employment-related outcomes of interventions aimed at sick-listed workers with anxiety disorders, depressive disorders, adjustment disorders, stress-related disorders, personality disorders and/or somatoform disorders were included. When studies were aimed at more than one of these disorders, they were classified as targeting sick-listed workers with CMDs. Employment-related outcomes were defined broadly as (1) time until RTW, (2) proportion of participants achieving RTW, (3) number of sick leave days and (4) self-reported work-readiness.The literature search yielded 3777 publications of which 42 (n=38 938) were included in the systematic review and 32 (n=9459) had appropriate data for the meta-analysis. Two authors independently screened the titles and abstracts, independently read the full text articles of identified studies and reviewed reference lists and newer publications citing identified literature. Interobserver agreement was calculated at each stage and disagreements were resolved by consensus. A meta-analysis of 32 studies was conducted. The primary outcome measure used in the meta-analysis was time until RTW. If not available, the proportion of participants who had achieved RTW was used. Studies using alternative outcome measures were included in the meta-analysis if the outcomes could be converted to standardised effect sizes for mean difference between the groups.
Nineteen of the included studies found positive effects of the tested interventions, but only 11 of these were significant. Six studies found negative effects, but only two of these effects were significant. Ten studies found no effect. The pooled effect size (95 % CI) was 0.14 (0.07 to 0.22), the results revealed a significant, but relatively small, positive effect of the included interventions. Number of components included in the intervention, whether the intervention included contact to the work place and the disorder targeted affected RTW. Workers sick-listed due to stress-related disorders showed the largest effects. Effect sizes from studies aimed at workers with the remaining diagnoses did not appear to be significantly different from the effect sizes from studies aimed at workers with CMD. The effectiveness of interventions did not appear to vary systematically across countries and meta-regressions were performed to estimate the moderating effect of age and the proportion of women. These variables had no significant moderating impacts on effect sizes.
The effect sizes varied according to number of components in the interventions. Interventions with 0 components did not significantly differ from interventions with 1 component (which had an effect size of 0.00). However, interventions with 2 and 3 or more components were associated with significantly larger effect sizes (0.36 and 0.25, respectively) compared with interventions with 1 component. Interventions that included contact to the work place showed significantly larger effect sizes compared with interventions including none of the identified components. Regarding other intervention characteristics, meta-regressions were conducted to estimate the moderating effect of timing of the intervention, the length of intervention and the study quality rating, but these variables were not associated with significant moderating impacts on effect sizes.